AIEEE 2010 (Offline)Question 1
Let $f:R\to R$ be a positive increasing function with $\lim_{x\to\infty}\frac{f(3x)}{f(x)}=1$. Then $\lim_{x\to\infty}\frac{f(2x)}{f(x)}=$
Limits & Continuity
Solution
$f$ increasing and positive gives $1\le\frac{f(2x)}{f(x)}\le\frac{f(3x)}{f(x)}\to1$, so the limit is $1$.